The general aim of my laboratory's research is to delineate the various steps in the glycosylation of proteins and to determine possible biological consequences of impaired glycosylation. Our approach is to isolate and characterize mammalian cell mutants defective in glycosylation. These mutants will allow us to catalog various reactions in the synthetic pathway, and to determine what effect an alteration in a particular reaction has on different glycoprotein products. Previously we determined that both the cells and membrane preparations of a concanavalin-A resistant Chinese hamster ovary cell line (B211) failed to glucosylate its oligosaccharide-lipid intermediates and protein. Presently, we are examining individual membrane-associated and soluble glycoproteins in this cell line. This study should help to elucidate the role of glucose in the biosynthesis of these glycoproteins and the biological consequences of this glycosylation defect.